1. Field of the Invention
The present invention relates to a steel manhole, and in particular to a steel manhole which is capable of implementing an easier communication cable installation under the ground and an easier check and maintenance of a drain pipe.
2. Description of the Background Art
Generally, a manhole is fabricated by pouring cement into a certain shape of a frame, and then the poured cement is hardened. Holes are formed at the left and right portions of the same, and a pipe way is formed in the holes, and then the cement is filled into the gaps between the holes and the pipe way.
However, the above-described work is complicated, and no work is done until the cement is fully hardened. In addition, since the formation period of the manhole is long, traffic must be detoured.
In addition, the construction site of the manhole is dangerous, and the cost for treating waste obtained after the manhole is fabricated is increased.
Since the water prevention is not guaranteed between the holes of the manhole and the connected portions of the pipe way, rain may penetrate into the manhole. In this case, water must be removed when maintaining the electric system or communication system.
Accordingly, it is an object of the present invention to provide a steel manhole which is capable of significantly decreasing the construction period and obtaining a recycling of the manhole and decreasing the amount of a source material.
To achieve the above object, there is provided a steel manhole which includes a steel box having a hole having a bolt hole and formed at an upper portion of the same, a height control pipe having a vertical longitudinal hole inserted into an inner diameter portion of the hole, a multi-hole lid for covering an upper portion of the height control pipe, a male screw formed at left and right portions of the steel box and having a male screw portion, and a female screw having a thread portion for being threaded with the male screw pipe.
The front and rear surfaces of the steel box are protruded, and a reinforcing steel is welded at an outer surface.
To achieve the above object, there is provided a steel manhole which includes a wave form steel pipe, a hole formed at an intermediate upper surface portion of the wave form steel pipe and having a plurality of holes at a side surface, a height control pipe inserted into the hole and having a plurality of height control holes at a portion corresponding to the hole, and a multi-hole lid inserted into the upper portion of the hole and covering the upper portion of the same.
The waveform steel pipe includes a gathering chamber at a bottom portion opposite to the hole formed on an upper surface.
Additional advantages, objects and features of the invention will become more apparent from the description which follows.